t = 0
t = 5
Explanation:
(-10t^2+50t)/(t^2+4t+3)
I'm making t into x so its not confusing with the plus sign
(-10x^2+50x)/(x^2+4x+3)
with (x^2+4x+3) :
what 2 numbers when multiplied make 3 and when added make 4 ?
they are 1 and 3
(x+1)(x+3)
(-10x^2+50x)/(x+1)(x+3)
(-10x(x-5))/(x+1)(x+3) =0
(-10t(t-5))/(t+1)(t+3)=0
t = 0
t = 5